This invention relates to a mobile communication device and a mobile communication system that includes the mobile communication device.
Recent attention has been focused on a Bluetooth technique which enables short range wireless data communication. Such a technique has been described, for example, in articles of Nikkei Electronics, published on Dec. 13, 1999 (pages 139 to 163) and Jan. 17, 2000 (pages 37 to 44). According to these articles, consideration has been made about applying the Bluetooth technique to a mobile telephone. Specifically, such a Bluetooth technique may make it possible to wirelessly couple a mobile telephone to a computer of a note book type. Thus, the Bluetooth technique can carry out wireless direct data communication of a short range that may be called short range wireless data communication hereinafter.
On the other hand, a wide variety of portable telephones have been proposed and widely used. For example, data communication has been carried out by the use of the mobile telephone through an internet, which enables download of various contents through the internet to the portable telephone. Such contents may be music, image, and any other information. Under the circumstances, the portable telephone serves as a multi-purpose tool.
For example, a portable telephone which can carry out data transmission has been described, for example, in Japanese Unexamined Patent Publication Nos. Hei 6-213998 (213998/1994), Hei 8-153075 (153075/1996), Hei 9-68566 (68566/1997), Hei 9-98475 (98475/1997), Hei 9-130861 (130861/1997), Hei 9-281212 (281212/1997), Hei 10-79971 (79971/1998), Hei 11-18159 (18159/1999), and Hei 11-113066 (113066/1999). The publications, have been directed to a portable telephone that may include a GPS (global positioning system) device and/or an IC card. In any event, each portable telephone carries out communication with an opponent or opponent device through at least one base station and therefore carries out indirect communication.
With reference to all the publications, no consideration has been made in the above-enumerated publications about using the portable telephone in common to data communication due to the Bluetooth.
There has been no disclosure made about any problems that might be caused to occur when a portable telephone has a data transmission function due to the Bluetooth in addition to a portable phone function.
For example, when a portable telephone can carry out direct communication in addition to indirect communication, power consumption might be seriously increased in the portable telephone. However, such a problem has not been previously recognized.
For example, when a portable telephone can carry out direct communication in addition to indirect communication, power consumption might be seriously increased in such a portable telephone. However, no teaching has not been pointed out in the prior art about such problems.